1 /******************************************************************************* 2 * 3 * Module Name: utmath - Integer math support routines 4 * 5 ******************************************************************************/ 6 7 /****************************************************************************** 8 * 9 * 1. Copyright Notice 10 * 11 * Some or all of this work - Copyright (c) 1999 - 2018, Intel Corp. 12 * All rights reserved. 13 * 14 * 2. License 15 * 16 * 2.1. This is your license from Intel Corp. under its intellectual property 17 * rights. You may have additional license terms from the party that provided 18 * you this software, covering your right to use that party's intellectual 19 * property rights. 20 * 21 * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a 22 * copy of the source code appearing in this file ("Covered Code") an 23 * irrevocable, perpetual, worldwide license under Intel's copyrights in the 24 * base code distributed originally by Intel ("Original Intel Code") to copy, 25 * make derivatives, distribute, use and display any portion of the Covered 26 * Code in any form, with the right to sublicense such rights; and 27 * 28 * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent 29 * license (with the right to sublicense), under only those claims of Intel 30 * patents that are infringed by the Original Intel Code, to make, use, sell, 31 * offer to sell, and import the Covered Code and derivative works thereof 32 * solely to the minimum extent necessary to exercise the above copyright 33 * license, and in no event shall the patent license extend to any additions 34 * to or modifications of the Original Intel Code. No other license or right 35 * is granted directly or by implication, estoppel or otherwise; 36 * 37 * The above copyright and patent license is granted only if the following 38 * conditions are met: 39 * 40 * 3. Conditions 41 * 42 * 3.1. Redistribution of Source with Rights to Further Distribute Source. 43 * Redistribution of source code of any substantial portion of the Covered 44 * Code or modification with rights to further distribute source must include 45 * the above Copyright Notice, the above License, this list of Conditions, 46 * and the following Disclaimer and Export Compliance provision. In addition, 47 * Licensee must cause all Covered Code to which Licensee contributes to 48 * contain a file documenting the changes Licensee made to create that Covered 49 * Code and the date of any change. Licensee must include in that file the 50 * documentation of any changes made by any predecessor Licensee. Licensee 51 * must include a prominent statement that the modification is derived, 52 * directly or indirectly, from Original Intel Code. 53 * 54 * 3.2. Redistribution of Source with no Rights to Further Distribute Source. 55 * Redistribution of source code of any substantial portion of the Covered 56 * Code or modification without rights to further distribute source must 57 * include the following Disclaimer and Export Compliance provision in the 58 * documentation and/or other materials provided with distribution. In 59 * addition, Licensee may not authorize further sublicense of source of any 60 * portion of the Covered Code, and must include terms to the effect that the 61 * license from Licensee to its licensee is limited to the intellectual 62 * property embodied in the software Licensee provides to its licensee, and 63 * not to intellectual property embodied in modifications its licensee may 64 * make. 65 * 66 * 3.3. Redistribution of Executable. Redistribution in executable form of any 67 * substantial portion of the Covered Code or modification must reproduce the 68 * above Copyright Notice, and the following Disclaimer and Export Compliance 69 * provision in the documentation and/or other materials provided with the 70 * distribution. 71 * 72 * 3.4. Intel retains all right, title, and interest in and to the Original 73 * Intel Code. 74 * 75 * 3.5. Neither the name Intel nor any other trademark owned or controlled by 76 * Intel shall be used in advertising or otherwise to promote the sale, use or 77 * other dealings in products derived from or relating to the Covered Code 78 * without prior written authorization from Intel. 79 * 80 * 4. Disclaimer and Export Compliance 81 * 82 * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED 83 * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE 84 * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE, 85 * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY 86 * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY 87 * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A 88 * PARTICULAR PURPOSE. 89 * 90 * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES 91 * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR 92 * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT, 93 * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY 94 * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL 95 * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS 96 * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY 97 * LIMITED REMEDY. 98 * 99 * 4.3. Licensee shall not export, either directly or indirectly, any of this 100 * software or system incorporating such software without first obtaining any 101 * required license or other approval from the U. S. Department of Commerce or 102 * any other agency or department of the United States Government. In the 103 * event Licensee exports any such software from the United States or 104 * re-exports any such software from a foreign destination, Licensee shall 105 * ensure that the distribution and export/re-export of the software is in 106 * compliance with all laws, regulations, orders, or other restrictions of the 107 * U.S. Export Administration Regulations. Licensee agrees that neither it nor 108 * any of its subsidiaries will export/re-export any technical data, process, 109 * software, or service, directly or indirectly, to any country for which the 110 * United States government or any agency thereof requires an export license, 111 * other governmental approval, or letter of assurance, without first obtaining 112 * such license, approval or letter. 113 * 114 ***************************************************************************** 115 * 116 * Alternatively, you may choose to be licensed under the terms of the 117 * following license: 118 * 119 * Redistribution and use in source and binary forms, with or without 120 * modification, are permitted provided that the following conditions 121 * are met: 122 * 1. Redistributions of source code must retain the above copyright 123 * notice, this list of conditions, and the following disclaimer, 124 * without modification. 125 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 126 * substantially similar to the "NO WARRANTY" disclaimer below 127 * ("Disclaimer") and any redistribution must be conditioned upon 128 * including a substantially similar Disclaimer requirement for further 129 * binary redistribution. 130 * 3. Neither the names of the above-listed copyright holders nor the names 131 * of any contributors may be used to endorse or promote products derived 132 * from this software without specific prior written permission. 133 * 134 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 135 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 136 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 137 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 138 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 139 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 140 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 141 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 142 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 143 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 144 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 145 * 146 * Alternatively, you may choose to be licensed under the terms of the 147 * GNU General Public License ("GPL") version 2 as published by the Free 148 * Software Foundation. 149 * 150 *****************************************************************************/ 151 152 #include "acpi.h" 153 #include "accommon.h" 154 155 156 #define _COMPONENT ACPI_UTILITIES 157 ACPI_MODULE_NAME ("utmath") 158 159 /* Structures used only for 64-bit divide */ 160 161 typedef struct uint64_struct 162 { 163 UINT32 Lo; 164 UINT32 Hi; 165 166 } UINT64_STRUCT; 167 168 typedef union uint64_overlay 169 { 170 UINT64 Full; 171 UINT64_STRUCT Part; 172 173 } UINT64_OVERLAY; 174 175 /* 176 * Optional support for 64-bit double-precision integer multiply and shift. 177 * This code is configurable and is implemented in order to support 32-bit 178 * kernel environments where a 64-bit double-precision math library is not 179 * available. 180 */ 181 #ifndef ACPI_USE_NATIVE_MATH64 182 183 /******************************************************************************* 184 * 185 * FUNCTION: AcpiUtShortMultiply 186 * 187 * PARAMETERS: Multiplicand - 64-bit multiplicand 188 * Multiplier - 32-bit multiplier 189 * OutProduct - Pointer to where the product is returned 190 * 191 * DESCRIPTION: Perform a short multiply. 192 * 193 ******************************************************************************/ 194 195 ACPI_STATUS 196 AcpiUtShortMultiply ( 197 UINT64 Multiplicand, 198 UINT32 Multiplier, 199 UINT64 *OutProduct) 200 { 201 UINT64_OVERLAY MultiplicandOvl; 202 UINT64_OVERLAY Product; 203 UINT32 Carry32; 204 205 206 ACPI_FUNCTION_TRACE (UtShortMultiply); 207 208 209 MultiplicandOvl.Full = Multiplicand; 210 211 /* 212 * The Product is 64 bits, the carry is always 32 bits, 213 * and is generated by the second multiply. 214 */ 215 ACPI_MUL_64_BY_32 (0, MultiplicandOvl.Part.Hi, Multiplier, 216 Product.Part.Hi, Carry32); 217 218 ACPI_MUL_64_BY_32 (0, MultiplicandOvl.Part.Lo, Multiplier, 219 Product.Part.Lo, Carry32); 220 221 Product.Part.Hi += Carry32; 222 223 /* Return only what was requested */ 224 225 if (OutProduct) 226 { 227 *OutProduct = Product.Full; 228 } 229 230 return_ACPI_STATUS (AE_OK); 231 } 232 233 234 /******************************************************************************* 235 * 236 * FUNCTION: AcpiUtShortShiftLeft 237 * 238 * PARAMETERS: Operand - 64-bit shift operand 239 * Count - 32-bit shift count 240 * OutResult - Pointer to where the result is returned 241 * 242 * DESCRIPTION: Perform a short left shift. 243 * 244 ******************************************************************************/ 245 246 ACPI_STATUS 247 AcpiUtShortShiftLeft ( 248 UINT64 Operand, 249 UINT32 Count, 250 UINT64 *OutResult) 251 { 252 UINT64_OVERLAY OperandOvl; 253 254 255 ACPI_FUNCTION_TRACE (UtShortShiftLeft); 256 257 258 OperandOvl.Full = Operand; 259 260 if ((Count & 63) >= 32) 261 { 262 OperandOvl.Part.Hi = OperandOvl.Part.Lo; 263 OperandOvl.Part.Lo = 0; 264 Count = (Count & 63) - 32; 265 } 266 ACPI_SHIFT_LEFT_64_BY_32 (OperandOvl.Part.Hi, 267 OperandOvl.Part.Lo, Count); 268 269 /* Return only what was requested */ 270 271 if (OutResult) 272 { 273 *OutResult = OperandOvl.Full; 274 } 275 276 return_ACPI_STATUS (AE_OK); 277 } 278 279 /******************************************************************************* 280 * 281 * FUNCTION: AcpiUtShortShiftRight 282 * 283 * PARAMETERS: Operand - 64-bit shift operand 284 * Count - 32-bit shift count 285 * OutResult - Pointer to where the result is returned 286 * 287 * DESCRIPTION: Perform a short right shift. 288 * 289 ******************************************************************************/ 290 291 ACPI_STATUS 292 AcpiUtShortShiftRight ( 293 UINT64 Operand, 294 UINT32 Count, 295 UINT64 *OutResult) 296 { 297 UINT64_OVERLAY OperandOvl; 298 299 300 ACPI_FUNCTION_TRACE (UtShortShiftRight); 301 302 303 OperandOvl.Full = Operand; 304 305 if ((Count & 63) >= 32) 306 { 307 OperandOvl.Part.Lo = OperandOvl.Part.Hi; 308 OperandOvl.Part.Hi = 0; 309 Count = (Count & 63) - 32; 310 } 311 ACPI_SHIFT_RIGHT_64_BY_32 (OperandOvl.Part.Hi, 312 OperandOvl.Part.Lo, Count); 313 314 /* Return only what was requested */ 315 316 if (OutResult) 317 { 318 *OutResult = OperandOvl.Full; 319 } 320 321 return_ACPI_STATUS (AE_OK); 322 } 323 #else 324 325 /******************************************************************************* 326 * 327 * FUNCTION: AcpiUtShortMultiply 328 * 329 * PARAMETERS: See function headers above 330 * 331 * DESCRIPTION: Native version of the UtShortMultiply function. 332 * 333 ******************************************************************************/ 334 335 ACPI_STATUS 336 AcpiUtShortMultiply ( 337 UINT64 Multiplicand, 338 UINT32 Multiplier, 339 UINT64 *OutProduct) 340 { 341 342 ACPI_FUNCTION_TRACE (UtShortMultiply); 343 344 345 /* Return only what was requested */ 346 347 if (OutProduct) 348 { 349 *OutProduct = Multiplicand * Multiplier; 350 } 351 352 return_ACPI_STATUS (AE_OK); 353 } 354 355 /******************************************************************************* 356 * 357 * FUNCTION: AcpiUtShortShiftLeft 358 * 359 * PARAMETERS: See function headers above 360 * 361 * DESCRIPTION: Native version of the UtShortShiftLeft function. 362 * 363 ******************************************************************************/ 364 365 ACPI_STATUS 366 AcpiUtShortShiftLeft ( 367 UINT64 Operand, 368 UINT32 Count, 369 UINT64 *OutResult) 370 { 371 372 ACPI_FUNCTION_TRACE (UtShortShiftLeft); 373 374 375 /* Return only what was requested */ 376 377 if (OutResult) 378 { 379 *OutResult = Operand << Count; 380 } 381 382 return_ACPI_STATUS (AE_OK); 383 } 384 385 /******************************************************************************* 386 * 387 * FUNCTION: AcpiUtShortShiftRight 388 * 389 * PARAMETERS: See function headers above 390 * 391 * DESCRIPTION: Native version of the UtShortShiftRight function. 392 * 393 ******************************************************************************/ 394 395 ACPI_STATUS 396 AcpiUtShortShiftRight ( 397 UINT64 Operand, 398 UINT32 Count, 399 UINT64 *OutResult) 400 { 401 402 ACPI_FUNCTION_TRACE (UtShortShiftRight); 403 404 405 /* Return only what was requested */ 406 407 if (OutResult) 408 { 409 *OutResult = Operand >> Count; 410 } 411 412 return_ACPI_STATUS (AE_OK); 413 } 414 #endif 415 416 /* 417 * Optional support for 64-bit double-precision integer divide. This code 418 * is configurable and is implemented in order to support 32-bit kernel 419 * environments where a 64-bit double-precision math library is not available. 420 * 421 * Support for a more normal 64-bit divide/modulo (with check for a divide- 422 * by-zero) appears after this optional section of code. 423 */ 424 #ifndef ACPI_USE_NATIVE_DIVIDE 425 426 427 /******************************************************************************* 428 * 429 * FUNCTION: AcpiUtShortDivide 430 * 431 * PARAMETERS: Dividend - 64-bit dividend 432 * Divisor - 32-bit divisor 433 * OutQuotient - Pointer to where the quotient is returned 434 * OutRemainder - Pointer to where the remainder is returned 435 * 436 * RETURN: Status (Checks for divide-by-zero) 437 * 438 * DESCRIPTION: Perform a short (maximum 64 bits divided by 32 bits) 439 * divide and modulo. The result is a 64-bit quotient and a 440 * 32-bit remainder. 441 * 442 ******************************************************************************/ 443 444 ACPI_STATUS 445 AcpiUtShortDivide ( 446 UINT64 Dividend, 447 UINT32 Divisor, 448 UINT64 *OutQuotient, 449 UINT32 *OutRemainder) 450 { 451 UINT64_OVERLAY DividendOvl; 452 UINT64_OVERLAY Quotient; 453 UINT32 Remainder32; 454 455 456 ACPI_FUNCTION_TRACE (UtShortDivide); 457 458 459 /* Always check for a zero divisor */ 460 461 if (Divisor == 0) 462 { 463 ACPI_ERROR ((AE_INFO, "Divide by zero")); 464 return_ACPI_STATUS (AE_AML_DIVIDE_BY_ZERO); 465 } 466 467 DividendOvl.Full = Dividend; 468 469 /* 470 * The quotient is 64 bits, the remainder is always 32 bits, 471 * and is generated by the second divide. 472 */ 473 ACPI_DIV_64_BY_32 (0, DividendOvl.Part.Hi, Divisor, 474 Quotient.Part.Hi, Remainder32); 475 476 ACPI_DIV_64_BY_32 (Remainder32, DividendOvl.Part.Lo, Divisor, 477 Quotient.Part.Lo, Remainder32); 478 479 /* Return only what was requested */ 480 481 if (OutQuotient) 482 { 483 *OutQuotient = Quotient.Full; 484 } 485 if (OutRemainder) 486 { 487 *OutRemainder = Remainder32; 488 } 489 490 return_ACPI_STATUS (AE_OK); 491 } 492 493 494 /******************************************************************************* 495 * 496 * FUNCTION: AcpiUtDivide 497 * 498 * PARAMETERS: InDividend - Dividend 499 * InDivisor - Divisor 500 * OutQuotient - Pointer to where the quotient is returned 501 * OutRemainder - Pointer to where the remainder is returned 502 * 503 * RETURN: Status (Checks for divide-by-zero) 504 * 505 * DESCRIPTION: Perform a divide and modulo. 506 * 507 ******************************************************************************/ 508 509 ACPI_STATUS 510 AcpiUtDivide ( 511 UINT64 InDividend, 512 UINT64 InDivisor, 513 UINT64 *OutQuotient, 514 UINT64 *OutRemainder) 515 { 516 UINT64_OVERLAY Dividend; 517 UINT64_OVERLAY Divisor; 518 UINT64_OVERLAY Quotient; 519 UINT64_OVERLAY Remainder; 520 UINT64_OVERLAY NormalizedDividend; 521 UINT64_OVERLAY NormalizedDivisor; 522 UINT32 Partial1; 523 UINT64_OVERLAY Partial2; 524 UINT64_OVERLAY Partial3; 525 526 527 ACPI_FUNCTION_TRACE (UtDivide); 528 529 530 /* Always check for a zero divisor */ 531 532 if (InDivisor == 0) 533 { 534 ACPI_ERROR ((AE_INFO, "Divide by zero")); 535 return_ACPI_STATUS (AE_AML_DIVIDE_BY_ZERO); 536 } 537 538 Divisor.Full = InDivisor; 539 Dividend.Full = InDividend; 540 if (Divisor.Part.Hi == 0) 541 { 542 /* 543 * 1) Simplest case is where the divisor is 32 bits, we can 544 * just do two divides 545 */ 546 Remainder.Part.Hi = 0; 547 548 /* 549 * The quotient is 64 bits, the remainder is always 32 bits, 550 * and is generated by the second divide. 551 */ 552 ACPI_DIV_64_BY_32 (0, Dividend.Part.Hi, Divisor.Part.Lo, 553 Quotient.Part.Hi, Partial1); 554 555 ACPI_DIV_64_BY_32 (Partial1, Dividend.Part.Lo, Divisor.Part.Lo, 556 Quotient.Part.Lo, Remainder.Part.Lo); 557 } 558 559 else 560 { 561 /* 562 * 2) The general case where the divisor is a full 64 bits 563 * is more difficult 564 */ 565 Quotient.Part.Hi = 0; 566 NormalizedDividend = Dividend; 567 NormalizedDivisor = Divisor; 568 569 /* Normalize the operands (shift until the divisor is < 32 bits) */ 570 571 do 572 { 573 ACPI_SHIFT_RIGHT_64 ( 574 NormalizedDivisor.Part.Hi, NormalizedDivisor.Part.Lo); 575 ACPI_SHIFT_RIGHT_64 ( 576 NormalizedDividend.Part.Hi, NormalizedDividend.Part.Lo); 577 578 } while (NormalizedDivisor.Part.Hi != 0); 579 580 /* Partial divide */ 581 582 ACPI_DIV_64_BY_32 ( 583 NormalizedDividend.Part.Hi, NormalizedDividend.Part.Lo, 584 NormalizedDivisor.Part.Lo, Quotient.Part.Lo, Partial1); 585 586 /* 587 * The quotient is always 32 bits, and simply requires 588 * adjustment. The 64-bit remainder must be generated. 589 */ 590 Partial1 = Quotient.Part.Lo * Divisor.Part.Hi; 591 Partial2.Full = (UINT64) Quotient.Part.Lo * Divisor.Part.Lo; 592 Partial3.Full = (UINT64) Partial2.Part.Hi + Partial1; 593 594 Remainder.Part.Hi = Partial3.Part.Lo; 595 Remainder.Part.Lo = Partial2.Part.Lo; 596 597 if (Partial3.Part.Hi == 0) 598 { 599 if (Partial3.Part.Lo >= Dividend.Part.Hi) 600 { 601 if (Partial3.Part.Lo == Dividend.Part.Hi) 602 { 603 if (Partial2.Part.Lo > Dividend.Part.Lo) 604 { 605 Quotient.Part.Lo--; 606 Remainder.Full -= Divisor.Full; 607 } 608 } 609 else 610 { 611 Quotient.Part.Lo--; 612 Remainder.Full -= Divisor.Full; 613 } 614 } 615 616 Remainder.Full = Remainder.Full - Dividend.Full; 617 Remainder.Part.Hi = (UINT32) -((INT32) Remainder.Part.Hi); 618 Remainder.Part.Lo = (UINT32) -((INT32) Remainder.Part.Lo); 619 620 if (Remainder.Part.Lo) 621 { 622 Remainder.Part.Hi--; 623 } 624 } 625 } 626 627 /* Return only what was requested */ 628 629 if (OutQuotient) 630 { 631 *OutQuotient = Quotient.Full; 632 } 633 if (OutRemainder) 634 { 635 *OutRemainder = Remainder.Full; 636 } 637 638 return_ACPI_STATUS (AE_OK); 639 } 640 641 #else 642 643 /******************************************************************************* 644 * 645 * FUNCTION: AcpiUtShortDivide, AcpiUtDivide 646 * 647 * PARAMETERS: See function headers above 648 * 649 * DESCRIPTION: Native versions of the UtDivide functions. Use these if either 650 * 1) The target is a 64-bit platform and therefore 64-bit 651 * integer math is supported directly by the machine. 652 * 2) The target is a 32-bit or 16-bit platform, and the 653 * double-precision integer math library is available to 654 * perform the divide. 655 * 656 ******************************************************************************/ 657 658 ACPI_STATUS 659 AcpiUtShortDivide ( 660 UINT64 InDividend, 661 UINT32 Divisor, 662 UINT64 *OutQuotient, 663 UINT32 *OutRemainder) 664 { 665 666 ACPI_FUNCTION_TRACE (UtShortDivide); 667 668 669 /* Always check for a zero divisor */ 670 671 if (Divisor == 0) 672 { 673 ACPI_ERROR ((AE_INFO, "Divide by zero")); 674 return_ACPI_STATUS (AE_AML_DIVIDE_BY_ZERO); 675 } 676 677 /* Return only what was requested */ 678 679 if (OutQuotient) 680 { 681 *OutQuotient = InDividend / Divisor; 682 } 683 if (OutRemainder) 684 { 685 *OutRemainder = (UINT32) (InDividend % Divisor); 686 } 687 688 return_ACPI_STATUS (AE_OK); 689 } 690 691 ACPI_STATUS 692 AcpiUtDivide ( 693 UINT64 InDividend, 694 UINT64 InDivisor, 695 UINT64 *OutQuotient, 696 UINT64 *OutRemainder) 697 { 698 ACPI_FUNCTION_TRACE (UtDivide); 699 700 701 /* Always check for a zero divisor */ 702 703 if (InDivisor == 0) 704 { 705 ACPI_ERROR ((AE_INFO, "Divide by zero")); 706 return_ACPI_STATUS (AE_AML_DIVIDE_BY_ZERO); 707 } 708 709 710 /* Return only what was requested */ 711 712 if (OutQuotient) 713 { 714 *OutQuotient = InDividend / InDivisor; 715 } 716 if (OutRemainder) 717 { 718 *OutRemainder = InDividend % InDivisor; 719 } 720 721 return_ACPI_STATUS (AE_OK); 722 } 723 724 #endif 725